The gut has its own independent nervous system.
Why it is true
The gut's "second brain" contains over 100 million neurons and can function independently from the brain.
Source: Integris Health / Neuroscience
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.